1. Field of the Invention
The present invention relates to a filter element and a process for manufacturing the same for use in an air cleaner for an internal combustion engine of an automobile.
2. Description of Related Art
Conventionally, a filter element for use in an air cleaner for an engine of an automobile is composed of a filter portion of a wave sheet and a flange portion framing the filter portion. Further, the air cleaner includes two housing members (case and cap) which construct a housing when assembled to each other.
When the filter element is assembled into an air cleaner having upper and lower housing members, the flange portion of the filter element is held between peripheral holding portions of the upper and lower housing members.
In the conventional air cleaner, a separate rubber gasket (seal member) is attached to the flange portion of the filter element to seal the holding portions of the housing members and the flange portion of the filter element, resulting in an increase in the number of parts of the air cleaner and the cost thereof. Further, the gasket must be removed every time the filter element is exchanged, thereby reducing the sealing performance.
If the flange portion of the filter element is directly inserted between each of the holding portions of the housing members the air cleaner without the gasket does not work because of poor sealing performance.
Further, EP 0692294A1 proposes a filter element having an integral flange portion. However, if the flange portion is inserted, as a seal member, between the upper and lower parts of the air cleaner housing members (or a cap and a case), the flange portion may deform under a high temperature because of the adhesive fiber included therein. Thus, when the filter element is re-assembled after cleaning, a clearance results between the flange portion and the parts of the air cleaner housing.
Particularly, as the thickness of the flange portion increases, the deformation increases.